<script setup>
import { onMounted, ref } from 'vue'
import axios from 'axios'
import powSet from './power-set'
// 商品数据
let pathMap = {}
const goods = ref({})
const getGoods = async () => {
  // 1135076  初始化就有无库存的规格
  // 1369155859933827074 更新之后有无库存项（蓝色-20cm-中国）
  const res = await axios.get('http://pcapi-xiaotuxian-front-devtest.itheima.net/goods?id=1369155859933827074')
  goods.value = res.data.result
  pathMap = getPathMap(goods.value)
  console.log(pathMap)
  initDisabledStatus(goods.value.specs, pathMap)
}
onMounted(() => getGoods())
const changeSelectedStatus = (item, val) => {
  if (val.disabled) return
  //item：同一排对象
  //val：当前点击项
  if (val.selected) {
    val.selected = false
  } else {
    item.values.forEach(valItem => valItem.selected = false);
    val.selected = true
  }
  updateDisabledStatus(goods.value.specs, pathMap)
  //产出sku对象
  const index = getSelectedValues(goods.value.specs).findIndex(item => item === undefined)
  if (index > -1) {
    console.log('信息不完整');
  } else {
    console.log('信息完整');
    //获取sku对象
  const key=getSelectedValues(goods.value.specs).join('-')
  const skuIds=pathMap[key]
  console.log(skuIds)
  //以skuId作为匹配项去goods.value.skus数组中找
  const skuObj=goods.value.skus.find(item=>item.id===skuIds[0])
  console.log(skuObj)
  }
}
// 生成有效路径字典
const getPathMap = (goods) => {
  const pathMap = {}
  //1.根据sku字段生成有效的sku数组
  const effectiveSkus = goods.skus.filter(sku => sku.inventory > 0)
  //2.根据有效的sku使用算法（子集算法）[1,2]->([1],[2],[1,2])
  effectiveSkus.forEach(sku => {
    //2.1获取匹配的valueName组成的数组
    const selectedValArr = sku.specs.map(val => val.valueName)
    //2.2 使用算法获取子集
    const valueArrPowerSet = powSet(selectedValArr)
    //3.把得到子集生成最终的路径字典对象
    valueArrPowerSet.forEach(arr => {
      //初始化key 数组join ->字符串 对象的key
      const key = arr.join('-')
      //如果已经存在当前key了 就往数组中直接添加skuId 如果不存在key 直接做赋值
      if (pathMap[key]) {
        pathMap[key].push(sku.id)
      } else {
        pathMap[key] = [sku.id]
      }
    })
  })
  return pathMap
}
//初始化禁用状态
const initDisabledStatus = (specs, pathMap) => {
  specs.forEach(specs => {
    specs.values.forEach(val => {
      if (pathMap[val.name]) {
        val.disabled = false
      } else {
        val.disabled = true
      }
    })
  })
}
//获取选中项的匹配数组
const getSelectedValues = (specs) => {
  const arr = []
  specs.forEach(spec => {
    //目标：找到values中selected为true的项，然后把它的name字段添加数组对应的位置
    const selectedVal = spec.values.find(item => item.selected)
    arr.push(selectedVal ? selectedVal.name : undefined)
  })
  return arr
}
//切换时更新禁用状态
const updateDisabledStatus = (specs, pathMap) => {
  specs.forEach((spec, index) => {
    const selectedValues = getSelectedValues(specs)
    spec.values.forEach(val => {
      //1把name字段的值填充到对应的位置
      selectedValues[index] = val.name
      //2 过滤掉undefined项使用的join方法形成一个有效的key
      const key = selectedValues.filter(value => value).join('-')
      //3 使用key取pathMap中进行匹配，匹配不上，则当前项禁用
      if (pathMap[key]) {
        val.disabled = false
      } else {
        val.disabled = true
      }
    })
  })
}
</script>

<template>
  <div class="goods-sku">
    <dl v-for="item in goods.specs" :key="item.id">
      <dt>{{ item.name }}</dt>
      <dd>
        <template v-for="val in item.values" :key="val.name">
          <!-- 图片类型规格 -->
          <img :class="{ selected: val.selected, disabled: val.disabled }" @click="changeSelectedStatus(item, val)"
            v-if="val.picture" :src="val.picture" :title="val.name">
          <!-- 文字类型规格 -->
          <span :class="{ selected: val.selected, disabled: val.disabled }" @click="changeSelectedStatus(item, val)" v-else>
            {{ val.name }}</span>
        </template>
      </dd>
    </dl>
  </div>
</template>

<style scoped lang="scss">
@mixin sku-state-mixin {
  border: 1px solid #e4e4e4;
  margin-right: 10px;
  cursor: pointer;

  &.selected {
    border-color: #27ba9b;
  }

  &.disabled {
    opacity: 0.6;
    border-style: dashed;
    cursor: not-allowed;
  }
}

.goods-sku {
  padding-left: 10px;
  padding-top: 20px;

  dl {
    display: flex;
    padding-bottom: 20px;
    align-items: center;

    dt {
      width: 50px;
      color: #999;
    }

    dd {
      flex: 1;
      color: #666;

      >img {
        width: 50px;
        height: 50px;
        margin-bottom: 4px;
        @include sku-state-mixin;
      }

      >span {
        display: inline-block;
        height: 30px;
        line-height: 28px;
        padding: 0 20px;
        margin-bottom: 4px;
        @include sku-state-mixin;
      }
    }
  }
}
</style>
